Beef mutagens

T. Nyhammar, S. Grivas, K. Olsson, and M. Jagerstad, Isolation and identification of beef mutagens (IQ compounds) from heated model systems of creatinine, fructose and glycine or alanine, in C, 1986, 323-327. 

Knize, M. G., Felton, J. S. The synthesis of the cooked-beef mutagen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine and its 3-methyl isomer. Heterocycles 1986, 24, 1815-1819. 

The second group of mutagenic and carcinogenic HAs comprises compounds that are formed at lower temperature and have been found in cooked meat and fish dishes, gravies, pan residues, broiled and fried beef, and... 

Galceran et al. (199) developed an SPE-HPLC method for the determination in beef extract of five mutagenic amines, namely Trp-P-1 (3-amino-1,4-dimethyl-5//-pyrido[4,3-fc]indole),... 

Mutagenic activity is also present in broiled herring, mackerel and sardine (11,12,22). In part, these mutagens were later identified as Trp-P-1 and Trp-P-2 (12) and IQ and 2-amino-3,4-dimethylimidazo [4,5-fJquinoline (Me-IQ)(13). In addition, Bjeldanes e t a. (23) have also reported mutagen formation in pan-fried fish, such as rock cod, sole, halibut, trout, salmon and red snapper. However, the mutagenic activity is low compared to that in beef. 

Spingarn et l1. (46) showed that the amount of fat present in ground beef was an important variable in mutagen formation. 

Figure 4. Mutagenicity of fried beef patties to TA98 with added S9 as a function of percentage fat in the beef (Ref. 46).

Figure 5. Reduction in observed mutagenic activity of ground beef basic extracts from patties cooked with several additives. Extracts were tested with TA98 and...

As would be expected from the results of studies on model systems, it has been found that foods with a high starch or sugar content may form genotoxic substances, but at a much lower level than meats or fish. Spingarn et al (65) showed that several common foods, in addition to beef, contained mutagens active for TA98 in the presence of S9 (Table V) Pariza et al. (66) found mutagenic activity in basic fractions of chicken broth, beef broth, rice cereal, bread crust, crackers, corn flakes, toast and cookies. 

Creatinine and Maillard Reaction Products as Precursors of Mutagenic Compounds Formed in Fried Beef... 

Table I summarizes the mutagenic activity in the meat experiment expressed in revertants per plate. Raw beef as well as the meat crumb contained no significant levels of mutagenic activity, that is below 20 revertants per plate, when corrected for spontaneous revertants. The mutagenic activity was found in the meat crust and required 9 activation. None of the samples assayed without S9 activation exceeded the values of spontaneous revertants and were therefore not included in the table.

Table II. Effect of creatinine concentrations on the mutagenic activity in crusts (dry matter) of fried beef. Creatine concentrations within parenthesis. Brown color as a measure of Maillard reaction products is given as absorbance at 375 nm per g dry matter...

Figure 3. Effect of glucose concentration on the mutagenic activity in fried beef...

Further research is necessary to identify these mutagens formed in the model system and to demonstrate their occurrence in the meat crust of fried or broiled beef. Also important is to show if these mutagens hav tumor-inducing effects in animal studies. 

M. Jagerstad, A. L. Reutersward, R. Oste, A. Dahlqvist, S. Grivas, K. Olsson, and T. Nyhammar, Creatinine and Maillard reaction products as precursors of mutagenic compounds formed in fried beef, in B, 1983, 507-519. 

Malonaldehyde, a major product of autoxidatlon of polyunsaturated fatty acids is a very reactive substance and reacts with amino acids, proteins and other chemical substances present in meats. Its concentration is generally determined by the 2-thlobarblturlc acid (TEA) test. Malonaldehyde may be used as an indicator for evaluation of the oxidative state of cooked meats. It has been reported that warmed-over flavor in beef is generally perceived when TEA number of cooked meats exceed numerical values of 0.5 to 1.0 (31). Malonaldehyde has also been implicated as having mutagenic and perhaps carcinogenic effects (32). Its presence further affects the rheological properties and texture of cooked meat products. Despite these, malonaldehyde has very little or no... 

P. Pais, E. Moyano, L. Puignou, M.T. Galceran, LC-APCI-MS as a routine method for the analysis of mutagenic amines in beef extracts, J. Chromatogr. A, 778 (1997) 207. 

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